This section provides background information related to the present disclosure which is not necessarily prior art.
From traditional black and white to color, from standard definition to high definition, from the 4K2K ultra high-definition to the future 8K4K, as display resolution upgrades, the amount of data required to be transmitted within an LCD TV increases as well. In particular, the amount of data transmitted between a display panel and a drive control circuit (such as a main drive control chip and a column drive control chip) is multiplied manyfold as the display resolution upgrades.
For example, a commonly used interface of a display panel is mini-LVDS, whose transmission rate is usually 300 MHz. Using the same transmission protocol for data transmission, when the display panel is a high definition panel, 16 data cables are needed; when the display panel is a 4K2K panel, 56 data cables are needed; and when the display panel is an 8K4K panel, 224 data cables are needed. In other words, the number of cables required for an 8K4K panel is 14 times as the number of cables required for a high definition panel.
Since it would worsen the reliability and the electrical performance (such as the electromagnetic compatibility, EMC) of an LCD television to increase the number of cables connected blindly, a point-to-point communication method using a high speed communication protocol is used to increase the data transmission rate, without increasing the number of cables connected, so that huge amount of data could be transmitted within an LCD television.
According to the high-speed protocol, the frequency synchronization process in the existing point-to-point method is: a pre-stage communication apparatus, when its operating frequency is unstable, by responding to a clock training request initiated by the post-stage communication apparatus due to recognition of the instability of operating frequency of the pre-stage communication apparatus, performs clock training on the post-stage communication apparatus, so that the operating frequency of the post-stage communication apparatus could stay the same as the operating frequency of the pre-stage communication apparatus, thus realizing frequency synchronization between the pre-stage communication apparatus and the post-stage communication apparatus; and after the clock training of the post-stage communication apparatus has succeeded, both communication apparatuses enter into working state to transmit valid data.